
/***********************************************************************

Copyright 2017 quantOS-org

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at:

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

***********************************************************************/
#ifndef _GETOPT_H
#define _GETOPT_H
 
 
#ifdef __cplusplus
extern "C" { 
#endif 
 
/* For communication from `getopt' to the caller.
 When `getopt' finds an option that takes an argument, 
 the argument value is returned here.
 Also, when `ordering' is RETURN_IN_ORDER, 
 each non-option ARGV-element is returned here.*/
 
extern char *optarg; 
 
/* Index in ARGV of the next element to be scanned.
 This is used for communication to and from the caller 
 and for communication between successive calls to `getopt'. 
 
 On entry to `getopt', zero means this is the first call; initialize.
 
 When `getopt' returns -1, this is the index of the first of the 
 non-option elements that the caller should itself scan. 
 
 Otherwise, `optind' communicates from one call to the next
 how much of ARGV has been scanned so far.*/ 
 
extern int optind; 
 
/* Callers store zero here to inhibit the error message `getopt' prints
 for unrecognized options.*/ 
 
extern int opterr; 
 
/* Set to an option character which was unrecognized.*/
 
extern int optopt; 
 
/* Describe the long-named options requested by the application. 
 The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
 of `struct option' terminated by an element containing a name which is
 zero. 
 
 The field `has_arg' is: 
 no_argument(or 0) if the option does not take an argument,
 required_argument(or 1) if the option requires an argument, 
 optional_argument(or 2) if the option takes an optional argument. 
 
 If the field `flag' is not NULL, it points to a variable that is set
 to the value given in the field `val' when the option is found, but 
 left unchanged if the option is not found.
 
 To have a long-named option do something other than set an `int' to 
 a compiled-in constant, such as set a value from `optarg', set the
 option's `flag' field to zero and its `val' field to a nonzero
 value (the equivalent single-letter option character, if there is 
 one).For long options that have a zero `flag' field, `getopt' 
 returns the contents of the `val' field.*/
 
struct option
{
#if defined (__STDC__) && __STDC__ 
const char *name;
#else
char *name;
#endif 
/* has_arg can't be an enum because some compilers complain about
 type mismatches in all the code that assumes it is an int.*/
int has_arg; 
int *flag; 
int val; 
}; 
 
/* Names for the values of the `has_arg' field of `struct option'.*/ 
 
#define no_argument 0
#define required_argument 1
#define optional_argument 2
 
extern int getopt_long (int argc, char *const *argv, const char *shortopts,
const struct option *longopts, int *longind);
extern int getopt_long_only (int argc, char *const *argv,
 const char *shortopts,
 const struct option *longopts, int *longind); 
 
/* Internal only.Users should not call this directly.*/
extern int _getopt_internal (int argc, char *const *argv,
 const char *shortopts,
 const struct option *longopts, int *longind,
 int long_only); 
extern int
 getopt (int argc,
 char *const *argv,
 const char *optstring);
 
#ifdef __cplusplus
}
#endif 
 
#endif /* _GETOPT_H */ 